1. Field of the Invention
The present invention relates to an image forming apparatus such as a copier, a printer, and a facsimile machine, and more particularly, to an image forming apparatus in which a document feed mechanism, an image reading mechanism, and an image forming mechanism are stacked within the image forming apparatus.
2. Discussion of the Background
Typically, image forming apparatuses include a manual sheet tray in addition to a sheet cassette from which transfer sheets are fed automatically. In such image forming apparatuses, if original documents from which image data is read and the transfer sheets onto which images are formed are placed on separate trays and are transported through separate sheet feeding paths, a large space and many components are required, which is not desirable. Consequently, several approaches, described below, have been proposed to solve such a problem.
In one known image forming apparatus, in order to reduce the number of components and use space efficiently, the image forming apparatus includes a dual purpose tray on which an original document (hereinafter simply “document”) as well as a transfer sheet can be manually set. Then, near the dual purpose tray, a sheet feeding path bifurcates into a document feeding path and a transfer sheet feeding path, and a sheet switching mechanism switches the sheet feeding path between them. Additionally, an image forming device that forms images on the transfer sheet is located under an image reading device that reads image data on the document, and the dual purpose tray is adjacent to and level with the image reading device.
However, in such an image forming apparatus, because the dual purpose tray is adjacent to and level with the image reading device, the configuration cannot solve the problem of how to use space efficiently in a horizontal direction.
In another known approach, an automatic document feeder (ADF) is located above a contact glass of a main body of the image forming apparatus, and the ADF can be lifted up and out of the way to expose the contact glass. Further, the ADF includes an openable/closable cover to open a transport path. When jamming of the document occurs in a transport path, the openable/closable cover is opened, removing the pressure exerted by a lifting plate.
However, in such an image forming apparatus, the number of components cannot be reduced because both a document tray and a transfer sheet tray are used.